Questions and Answers:

How is the base of a swimming pool created ?

The base is formed as a slab, install hydrostatic valve and pipework, place reinforcement as per engineering drawings ( you can download pool engineering drawings by registering and logging back in ) Place starter bars to the perimeter and then pour the slab with or without slope for the shallow and deep end. it’s your choice.

Why is it important to waterproof ?

As a builder, owner, architect or engineer, waterproofing is the most important requirement. You wouldn’t put bricks, blocks or a timber frame in position and expect it to be waterproof.

Likewise with Insulated Concrete Forms.

The waterproof barrier, either spray on liquid or sticky back sheet membranes with a protection board and/or cell drain acts as a cavity to drain the water down to your agricultural silt or sock wrapped drainage system. Covered with the appropriate drainage gravel and geotech fabric to again protect the drainage system from silt build up and to keep hydrostatic pressure of water off the wall.

Although, there are plastic formwork systems that claim to be a 100% waterproof, logic and common sense should always be applied which is why waterproofing is always important.

Some other considerations are the structural longevity of your building in the long term due to corroded structural reinforcement and the ability to repair and mitigate water or damp ingress into your habitable basement where valuable heirlooms, photographs or metal machinery is usually stored and not to mention your health!

Is ZEGO suitable for load bearing walls ?

The reinforced concrete core is the load bearing wall and the ZEGO is simply stay in place form work for casting the concrete to the engineers specification for your structure.

Rebate or No rebate in the slab ?

A rebate is not required as it’s a non cavity wall and the external finishes must extend 50mm past the slab as per the NCC.

Can metal cladding be fixed with battens on the 150 Series ? if so does the ZEGO block need to be sealed ?

Yes, batten the wall then fix the metal cladding. Seal the bottom of the wall with a metal capping and install an approved termite barrier.

If using ZEGO as a retaining wall, can tiles be fitted directly to product without rendering first ?

Make sure first that you have good drainage behind the wall. Yes you then simply apply your preferred acrylic tile adhesive, then lay your tiles, grout up your joints and clean up.

What about impact resistance with the render layer over the polystyrene ?

Reinforced Acrylic Render ( with or without texture) is the most commonly used finish and will provide an impact resistance surface able to resist all normal treatment associated with domestic and commercial constructions. Installation Firstly, brush down the surface to remove any debris Trowel on 4mm of base coat acrylic render (render to comply with CA26 Compliance) Roll out the reinforcement mesh for the render and trowel onto the surface Do not staple the mesh to the wall Overlap the slabs edge by 50mm minimum Cut 45 deg from the corner of the window openings Measure the reveal back to the windows, then measure, cut the mesh and fold back onto the reveals Ensure you reinforce the corners with additional reinforcement mesh Trowel on another 4mm of base coat On completion, an 8mm base coat with reinforcement mesh in the center for impact resistance

How can you create recesses on internal walls for display objects & uplights ?

Yes and this is simple to do. Here are a couple of examples. – Prior to plaster boarding the walls simply remove the foam surface and this will make a recess. Plaster the recess and you have a nice niche for artwork, photo frames etc. – If you require a deeper niche, simply place form work to form the niche prior to concreting – If you require downlights or uplights to the opening you again form out for these

How do you easily hang a picture on an internal wall ?

Use the normal picture hook ( these have a hole at 45deg) and nail into the plasterboard. The plasterboard will take the weight of pictures and wall hangings up to 10-15kg. For heavier items simply mount back to the concrete core.

Does ZEGO give off toxic fumes during a fire ?

Comments: At 600 Deg C ZEGO F grade flame retardant EPS will begin to melt. ZEGO Is made of 98% air and there is less Parts Per Million PPM than that of hardwood when burnt. As with burning timber toxic fumes are given off. ZEGO Complies with all building codes in Australia and World Wide and unlike timber ZEGO’s uses self extinguishing F grade EPS Flame Retardant foam

How can I learn more ?

Please visit this page.

What does it cost ?

A builder can build the external walls of your home in ZEGO for the same cost as a brick veneer home!

However, benefits of ZEGO vs Brick:

  • A ZEGO Insulate Concrete Form Home will save you 50% to 80% of your annual heating and cooling costs. Thereby, reducing the green boldhouse emissions from the power stations as they don’t have to produce as much power for ZEGO home owners.
  • ZEGO Homes are 6 to 9 times stronger than a traditional home due to the reinforced concrete core.
  • Cyclone rating is easily achieved.
  • Speed of construction is 1 to 1.5 weeks faster per floor level.
  • Less labour to be organized.
  • Easy clean up.
  • Simple installation of ducted vacuum, plumbing and electrical / Data Services without structural damage.
  • Quieter and more peaceful to live in.
  • Greater resale value as energy efficient homes become more popular.

How do you install architraves and skirting boards ?

These are simply installed 1-Applying NO More Nails, Max Bond or ZEGO’s adhesive foam spray to the back of the board. 2-After positioning shoot “T” nails at 45deg into the board and through the plasterboard. 3-If there is a bow in the board simply place a spreader from one side of the room to the board to hold in place until the adhesive has cured. 4-This will hold the board in place until the adhesive has cured. 5-The other side of the architraves that are mounted on the windows timber reveal can be nailed as normal.

What are the benefits of ZEGO ?

  • Service and Professionalism.
  • Male and Female Diamond interlock eliminates slippage during construction and during the concrete pour.
  • Patented Dovetailed Grooves for render and plasterboard support.
  • 300mm high coursing to suit door, window and ceiling heights 2100mm – 2400mm – 2700mm – 3000mm etc.
  • 50mm interlock and intersect.
  • Closed end and open end forms.
  • Patented Wall Brace Scaffolding System.
  • Save 50% to 80% of heating and cooling costs year after year.
  • Significantly save on material handling and labour onsite.
  • Replaces Brickwork and the frame in one process.

Formwork to Window and Door Openings?

The following options and variations are available to you;

  • 18mm plywood stripped to width of ZEGO wall form ie 200 Series forms are 190mm wide
  • Cut a 100 x 50 timber the width of the opening and nail or screw the plywood to the 100mm face
  • Cut some extra plywood 300mm x 190mm for base plates that sit on the window sill (NOTE: Not needed for door openings or full height windows)
  • Now cut precisely 100 x 50mm Props between the top of the baseplate and the underside of the 100 x 50 at the head (NOTE: If these props are too long, they will open up the course line of the forms)
  • If more than 300mm lintel height, foam up both sides of the head form


  • Use wide timbers eg planks cut to length for head timber
  • Follow item 3 to 5 above

Options (Ideal for the contractor with multiple projects)

  • Folded sheet metal cut to length or telescopic 1.2mm thickness
  • Follow item 3 to 5 above

How do you install windows and door frames ?

Firstly, it does not make sense to build an energy efficient building, then remove the foam insulation on the reveals when installing window and door frames!

Installation of Window and Door Frames

  • The opening should be approximately 10mm larger around all the window or door frames
  • Leave the foam in place and foam in using ZEGO window and door foam
  • Wedge the frame square and plumb in the opening of the insulate concrete forms
  • Make sure that any reveals are 15mm inside the room. This is to allow for the 10mm plasterboard and the 5mm air gap where the cornice cement is
  • With sliding windows and doors open the slider a little so that you can rack the frame to have the slider and frame meet parallel
  • Now tack the frame in place in the corners and at 600mm maximum centers using ZEGO window and door foam (Dries in approx one hour)
  • Proceed with installation of other frames in the building for approx one hour
  • Return to the first frame, check it is still square, in wind and plumb
  • If all OK, remove the wedges
  • Starting at the top of the window frame, spray ZEGO window and door foam in a continuous motion around the entire perimeter of the frame
  • Allow to dry and proceed with the other frames in the building for approx one hour
  • Repeat the full seal around the outside of the frame
  • Cut the excess foam off using a razor blade at the stage of rendering the walls or installing plasterboard


  • Do not seal both sides at once, or foam will get all over the frame and you will use more foam than necessary
  • The foam seal should be neat
  • Do not trim off any excess foam until you are installing the render or the plasterboard

How do you install overhead cupboards ?

Prior to plaster boarding the walls you simply mark out the cupboard location and remove 100mm wide strip of foam back to the concrete core. Mount the timber e.g. Glue with No More Nails, Max Bond or ZEGO Adhesive spray foam or bolt or use nail gun. Then install plasterboard and mount cupboard using wood screws as normal. Mounting items after plasterboard. Use plastic conduit or gal water-pipe as a spacer. Drill hole in plasterboard and foam back to concrete face. Place conduit or water pipe in hole. Drill masonry anchor in the centre and mount your item e.g. Clothes dryer or kitchen cupboards. When you tighten the bolts they will compress on the spacer conduit or water pipe and not compress or affect the plasterboard. Spacer length = plasterboard + foam thickness back to the concrete face.

Top Plate ?

Top Plate / Pitching Plate Setup

Use 10mm galvanized cup head bolts (length = top plate thickness + 15mm + length down to below top bond beam steel)

Insert it through an off cut of foam 45mm = Top plate thickness

This foam sits on top of the ZEGO wall and stops the bolt from sinking into the wet concrete. It also keeps it centred and protects the thread

Which ZEGO Insulate Concrete Form ICF Series should I use ?

150 Series: For up to two storeys with Timber first floor only. For areas with wind load of 41mps or less.

200 Series: Up to three levels above grade with concrete suspended slabs between levels.

250 Series: Ideal for below grade retaining walls and multiple level construction. Pool, water tanks, and civil works pits etc.

Fire Form: Available in a choice of insulating thickness and core width. As the name suggests, a fully certified fire rated form system for party walls, boundary walls and fire separation spandrels.

ReFORM: A fully strippable and reusable formwork system for basement carparks, watertanks, swimming pools and for clients who require an external solid concrete surface to the outside of their building. ReFORM can be used in conjunction with ZEGO Fire Form insulating panels which provide not only insulation but a service duct area for the plumbing and electrical/data services to run in without structural damage to the concrete core.